Whereby the end user, at runtime, can drag-and-drop controls, widgets or items from a Toolbox onto a diagram or form - with the ability to resize and move these controls as well as modify properties belonging to the items. Properties would include things like background color, text, font, image, and so on.

I also realise that there is no native Qt PropertyGrid style widget due to the features of the C/C++ language when compared to the properties of a C# class. However, given the power of the Qt metaObject system, this wouldn't be too much trouble to implement.

Having had a play around with the DiagramScene example Qt application, this is indeed a very good start. I have, however, realised that there is a lot of work in implementing such a widget so if there is something off-the-shelf which can be used then I'd much prefer to go down this route.

Has anyone had any experience with any such widgets? Any hints would be greatly appreciated.